\begin{tikzpicture}[shorten >=1pt,->]
  \tikzstyle{vertex}=[circle, minimum size=17pt,inner sep=1pt]

  \node[vertex] (P) {P};
  \node[vertex, below of= P] (S) {S};
  \node[vertex, right of= S, yshift= -0.5cm] (S1) {S};
  \node[vertex, left of= S, yshift= -0.5cm] (ST) {St};
  \node[vertex, below of= S] (PC) {;};
  \node[vertex, below of= S1] (L) {$\lambda$};
  \node[vertex, below of= ST] (E) {E};
  \node[vertex, below of= E] (A) {A};
  \node[vertex, right of= A, yshift= -0.5cm] (B) {B};
  \node[vertex, left of= A, yshift= -0.5cm] (A1) {A};
  \node[vertex, left of= B, yshift= -0.5cm] (M) {$-$};
  \node[vertex, right of= B, yshift= -0.5cm] (B1) {B};
  \node[vertex, below of= B1] (C) {C};
  \node[vertex, below of= C] (D) {D};
  \node[vertex, below of= D] (I) {\id};
  \node[vertex, below of= A1] (B2) {B};
  \node[vertex, below of= B2] (C2) {C};
  \node[vertex, below of= C2] (D2) {D};
  \node[vertex, below of= D2] (I2) {\id};

  \node[vertex, right of= P, node distance= 6cm] (P1) {P};
  \node[vertex, below of= P1] (S2) {S};
  \node[vertex, right of= S2, yshift= -0.5cm] (S3) {S};
  \node[vertex, left of= S2, yshift= -0.5cm] (ST1) {St};
  \node[vertex, below of= S2] (PC1) {;};
  \node[vertex, below of= S3] (L1) {$\lambda$};
  \node[vertex, below of= ST1] (E1) {E};
  \node[vertex, right of= E1, yshift= -0.5cm] (A2) {A};
  \node[vertex, left of= E1, yshift= -0.5cm] (E2) {E};
  \node[vertex, below of= E1] (M1) {$-$};
  \node[vertex, below of= A2] (B3) {B};
  \node[vertex, below of= B3] (C3) {C};
  \node[vertex, below of= C3] (D3) {D};
  \node[vertex, below of= D3] (I3) {\id};
  \node[vertex, below of= E2] (A3) {A};
  \node[vertex, below of= A3] (B4) {B};
  \node[vertex, below of= B4] (C4) {C};
  \node[vertex, below of= C4] (D4) {D};
  \node[vertex, below of= D4] (I4) {\id};

  \node[vertex, above of= P] (shift) {$\alpha=$ \id \, $-$ \id \, utilizando d25};
  \node[vertex, above of= P1] (reduce) {$\alpha=$ \id \, $-$ \id \, utilizando r21};

  \path (P) 	edge node[anchor=north,above]{}(S)
	(S) 	edge node[anchor=north,above]{}(ST)
	(S) 	edge node[anchor=north,above]{}(PC)
	(S) 	edge node[anchor=north,above]{}(S1)
	(S1) 	edge node[anchor=north,above]{}(L)
	(ST) 	edge node[anchor=north,above]{}(E)
	(E) 	edge node[anchor=north,above]{}(A)
	(A) 	edge node[anchor=north,above]{}(A1)
	(A) 	edge node[anchor=north,above]{}(B)
	(B) 	edge node[anchor=north,above]{}(M)
	(B) 	edge node[anchor=north,above]{}(B1)
	(B1) 	edge node[anchor=north,above]{}(C)
	(C) 	edge node[anchor=north,above]{}(D)
	(D) 	edge node[anchor=north,above]{}(I)
	(A1) 	edge node[anchor=north,above]{}(B2)
	(B2) 	edge node[anchor=north,above]{}(C2)
	(C2) 	edge node[anchor=north,above]{}(D2)
	(D2) 	edge node[anchor=north,above]{}(I2)
	(P1) 	edge node[anchor=north,above]{}(S2)
	(S2) 	edge node[anchor=north,above]{}(ST1)
	(S2) 	edge node[anchor=north,above]{}(PC1)
	(S2) 	edge node[anchor=north,above]{}(S3)
	(S3) 	edge node[anchor=north,above]{}(L1)
	(ST1) 	edge node[anchor=north,above]{}(E1)
	(E1) 	edge node[anchor=north,above]{}(E2)
	(E1) 	edge node[anchor=north,above]{}(M1)
	(E1) 	edge node[anchor=north,above]{}(A2)
	(A2) 	edge node[anchor=north,above]{}(B3)
	(B3) 	edge node[anchor=north,above]{}(C3)
	(C3) 	edge node[anchor=north,above]{}(D3)
	(D3) 	edge node[anchor=north,above]{}(I3)
	(E2) 	edge node[anchor=north,above]{}(A3)
	(A3) 	edge node[anchor=north,above]{}(B4)
	(B4) 	edge node[anchor=north,above]{}(C4)
	(C4) 	edge node[anchor=north,above]{}(D4)
	(D4) 	edge node[anchor=north,above]{}(I4);


\end{tikzpicture}

